Petroleum oil compositions



Patented Dec. 16, 1947 PETROLEUM OIL COMPOSITIONS Albert G. Rocchini,Aspinwall, and. Charles Byron Pattinson, Jr., Oakmont, Pa., assignors toGulf Research & Development Company, Pittsburgh, Pa., a corporation ofDelaware No Drawing. Application November 26, 1945, Serial No. 630,983

. 1 This invention relates to novel lubricating oil compositionscontaining stabilizers and more particularly to mineral oil compositionsthat contain an inhibitor effective to retard halogenation thereof.

It is well known that petroleum oils can be chlorinated. However, thereare some situations in which it is desired to employ a petroleum oilwhere it will be in contact with gaseous chlorine and still not reacttoo extensively therewith. This problem arises for instance inconnection with the operation of gas compressors and vacuum pumps usedto handle gases containing chlorine. In

3 Claims. (01. 252-52) bricating oils is disadvantageous, since whensaid oils are chlorinated their viscosities increase greatly, anddecomposition products are formed; hence their effectiveness as mediumsfor lubricating, cooling and maintaining liquid seals in gas compressorsand vacuum pumps becomes greatly diminished.

It is accordingly an object of this invention to provide suitable liquidmediums capable of lubricating, cooling and maintaining liquid seals ingas compressors and vacuum pumps, the effectiveness of which will notsubstantially diminish if said gas compressors and vacuum pumps are usedto handle gases containing chlorine. A further object is to provideimproved mineral oil compositions, the viscosities of which do notrapidly and greatly increase when said mineral oil compositions come incontact with gaseous chlorine and which are otherwise stable in thepresence of chlorine under the conditions of use. A still further objectis to provide a stabilized mineral oil composition containing aninhibitor effective to retard chlorination thereof. Another object is toprovide a mineral oil composition containing an inhibitor capable ofreducing the susceptibility of said mineral oil to chlorination,

which oil composition can be reclaimed after use by treating it withclay without any substantial loss of its ability to resist chlorination.Other objects will appear hereinafter.

These objects are accomplished in accordance with the followinginvention by providing a mineral oil composition comprising a majoramount of a petroleum lubricating oil and a minor amount of.ortho-cyclohexylphenol sufiicient to retard halogenation of saidpetroleum lubricating oil. Ifhis invention is applicable to bothparafiinic and naphthene-type lubricating oils. It is particularlyapplicable to lubricating oils having a viscosity ranging from to 450Saybolt Universal seconds at 100 F. Ordinarily the addition of from 0.25to 2.0 per cent by weight of ortho-cyclohexylphenol to such an oil willsuffice to substantially reduce the susceptibility of the oil tochlorination.

It has been found that a petroleum lubricating oil which has been highlyrefined in the presence of anhydrous aluminum chloride and which has ahigh viscosity index of the order of 100 and a viscosity of aboutSaybolt Universal seconds at 100 F. is a very effective lubricant for avacuum pump. However, if said pump is used to handle gases containingchlorine this lubricating oil deteriorates greatly and its Viscosityincreases greatly. A mineral oil composition containing 0.5 per cent byweight of ortho-cyclohexylphenol added to a petroleum lubricating oilhaving the properties just mentioned is not readily attacked bychlorine. When this oil composition containing ortho-cyclohexylphenol isused to lubricate and facilitate the operation of a vacuum pump that .ishandling gases containing chlorine, it does not readily deteriorate andits viscosity increases slowly in small increments.

It has been found that the addition of orthocyclohexylphenol to amineral oil lubricant materially improves its color stability.

Furthermore, it has been found that petroleum lubricating oilscontaining ortho-cyclohexylphenol as a chlorination inhibitor can bereclaimed by heating them with fullers earth and that the reclaimed oilsare still resistant to chlorination. This is important because it is aroutine operation to reclaim vacuum pumpoils by passing them through afullers earth filter at a temperature of 210 to 220 F. Persistence ofthe inhibiting ffect after said clay treatment is obviously verydesirable when the oils' are to be used after reclaiming in places wherethey will come in contact with chlorine.

In determining whether a given oil composition containing a known amountof a chlorination inhibitor can be heated with clay as is done in an oilreclaiming operation without substantial loss of its ability to resistchlorination, the following experimental procedure is employed. Ten percent by weight of powdered fullers earth is added to an oil compositioncontaining a chlorination inhibitor at temperatures between 210 and 220F. to drive off any water, and the oil is stirred vigorously for tenminutes. The mixture is then immediately filtered twice with the help ofan-asbestos type of filter aid. The oil composition thus treated maythen be tested by the procedure set forth in the following paragraph tosee if it is sufiiciently stabilized againstv chlorination.

In determining whether a given oil composition containing a known amountof a, chlorination inhibitor is sufficiently stabilized againstchlorination, the following experimental procedure is employed. Aplurality of 80 c. 0. samples of the oil composition containing aninhibitor are placed in 100 c. c. graduated cylinders, and 8 c. c. ofdistilled water is added to each cylinder. Each of the samples is shakenvigorously, and 12 inches each of No. 20 American gauge copper andv ironwires coiled together are immedi ately introduced into each cylinder,being suspended in the emulsion from the top of each cylinder. Freegaseous chlorine is then bubbled through each sample at the rate of 1400c. e. per hour. At hourly intervals chlorination of one, of. the samplesis discontinued, and the copper and iron wires are removed therefrom.After chlorination has been discontinued on a given sample it is allowedto sit until the oil reaches room temperature. The oil is decanted fromthe water and then blown with free nitrogen until all free chlorine hasbeen eliminated. It is usually necessary to blow with nitrogen for abouttwo, hours before the oil no longer emits an odor of chlorine. Eachsample is then analyzed to findithe amount of chlorine taken up by theoil, and its viscosity is determined by A. S. T. M. method D 88-44. Inthis way one can determine the amount of chlorine absorption and theviscosity change at. hourly intervals, and these data can be plotted incurves if desired.

When a petroleum lubricating oil that has been refined in the presenceof anhydrous aluminum chloride, which has a viscosity index of about 100and a viscosity of about 170 Saybolt Universal seconds at 100 F., andwhich contains no inhibitors is chlorinated and tested in accordancewith the procedure set forth inthe preceding paragraph, it is found thatafter five hours of chlorination it has absorbed 11.3 per centofchlorine and its viscosity in Saybolt Universal seconds at 100 F. hasincreased 135 per cent. When to the same oil there is added 0.5 per centby weight ofortho-cyclohexylphenol, it is found that after five hours ofchlorination it has absorbed only 5.4 per cent of chlorine and itsviscosity in Saybolt Universal seconds at 100 F. has increased only 35per cent. Furthermore, when the same oil containing 0.5 per cent byweight of ortho-cyclohexylphenol has been heated with fullers earth asdescribed hereinabove, it is found that after five hours of chlorinationit has absorbed only 5.9 per cent of chlorine and its viscosity inSaybolt Universal seconds at F. has increased only 40 per cent. It cantherefore be seen that ortho-cyclohexylphenol materially retardschlorination of this lubrioating oil.

Resort may be had to such variations and equivalents of this inventionas come within the spirit of the invention and the scope of the appendedclaims.

What we claim is:

1. A mineral oil composition comprising a. major amount of a petroleumlubricating oil and a small amount of ortho-cyclohexylphenol sufllcientto retard halogenation of said petroleum lubricating oil.

2. A mineral oil composition comprising a major amount of a petroleumlubricating oil having a viscosity lying in the range from about toabout 450 Saybolt Universal seconds at 100 F. and from 0.25 to 2.0 percent by weight of ortho-cyclohexylphenol to retard chlorination of saidpetroleum lubricating oil.

3. A mineral oil composition suitable for facilitating the operation ofa. vacuum pump that is handling gases containing chlorine comprisingabout 99.5 per cent of a highly parahinic petroleum lubricating oilhaving a viscosity of about Saybolt Universal seconds at 100 F., andabout 0.5 per cent of ortho-cyclohexylphenol to retard chlorination ofsaid petroleum lubricating oil.

ALBERT G. ROCCHINI. CHARLES BYRON PATTINSON, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date Re. 19,512 Bjerregard Apr. 2,1935 1,106,144 Harrison Aug. 4. 1914 1,492,391 McQuaid Apr. 29, 19241,784,359 Kaegebehn Dec. 9, 1930 1,884,559 Calcott Oct. 25, 19321,951,207 Rather Mar. 13, 1934 2,008,680 Carlisle July 23, 19352,044,318 Mills June 16, 1936 2,061,111 Stevens Nov. 17, 1936 2,155,723Levine Apr. 25, 1939 2,319,261 Pitman May 18, 1943 OTHER REFERENCESCarlisle, Stability of Chlorohydrocarbons, Ind. Eng. Chem., Oct. 1932,pages 1164-1168.

